A turbogroup, as is used in a power generating plant for power generation, customarily comprises a compressor for compressing combustion air, a combustion chamber for combusting a fuel with combustion air, and also a turbine in which the hot combustion exhaust gases are expanded, performing work. During operation of such energy conversion units, the formation of pollutant emissions is problematical. Therefore, the requirement for reducing the formation of pollutant emissions, especially of NOx emissions, permanently exists. The formation of NOx emissions has a strong connection to the temperature and to the pressure of the combustion process, wherein the NOx emissions increase superproportionally with increasing temperature or increasing pressure.
Instead of natural gas or instead of liquid fuels diluted with water, in principle it is known to use a fuel, the reactivity of which is higher or greater than that of natural gas. The use of highly reactive fuels already enables stable combustion reactions at lower temperatures. In practice, however, such highly reactive fuels are relatively strongly diluted, for example with water vapor or with nitrogen gas, in order to avoid an excessive temperature increase as a result of the combustion reaction. At the same time, these measures reduce the flame propagation speed, as a result of which the risk of a flame flashback can especially be reduced and therefore the operational safety of the turbogroup can be increased.
The introduction of water vapor into the fuel, however, is associated with a high cost. For example, the water must have comparatively high cleanliness in order to be able to add it to a fuel supply system of the turbogroup without any problem. Furthermore, the water or the water vapor must be brought to a comparatively high pressure, specifically to the compression pressure of the compressor, as a result of which a corresponding energy is required which ultimately reduces the overall efficiency of the turbogroup.